A conventional electro-photographic type image forming apparatus known in the art includes a process frame and a transfer belt. The process frame accommodates the plurality of the process cartridges that include photosensitive drums for yellow, magenta, cyan and black, respectively. The transfer belt is disposed in confrontation with the all photosensitive drums.
There is an electro-photographic type image forming apparatus in which a process frame accommodating all process cartridges is moved upward for positioning the photosensitive drums with respect to the transfer belt. More specifically, the process frame accommodating the plurality of the process cartridges is movable inside and outside of a main housing through an opening of the main housing. In the interlocking relation with the operation through the opening, a side opposite to the opening, i.e., a deep side is also operated, so that the process frame positioned inside the main housing is lifted upward. Accordingly, all of the process cartridges are lifted upward, thereby positioning the photosensitive drums with respect to the transfer belt.